I use a bottle, (OMM Ultra Bottle) with a convertube which replaces the cap with a tube system. The bottle goes into the side pocket of my UltaAspire Omega. Gives me the convenience of a bladder with the ease of refillling of a bottle!
Has worked brilliantly so far, shorter runs I'll use a handheld - the best ones I've found are the Ultimate Direction ones with the "kicker valve"
MT110's for me on everything from road to snowy mountains and 5k to 100 miles. Still in the black and yellow colourway after stockpiling from Sports Direct @ £35 / pair
Getting more into my Vibram Sprints for shorter / speed sessions and will probably pick up a pair of trail VFFs sooner-or-later and slowly transition that way.
Light and low-profile suits me, I'd agree that the tread on the MT110's isn't brilliant in really muddy stuff - especially steep and muddy, I nearly killed myself at the CTS Exmoor Ultra last weekend on the cliff path